Calculate the number of grams of copper(I) oxide reacted and the number of grams of copper and sulfur dioxide produced when 20 g of copper(I) sulfide is reacted?

Here’s what I got.
The first thing to do here is make sure that you’re working with a balanced chemical equation, which in this case looks like this
##”Cu”_ 2″S”_ ((l)) + 2″Cu” _ 2″O”_ ((l)) -> 6″Cu”_ ((l)) + “SO”_ (2(g))##
Molten copper(I) sulfide, ##”Cu”_2″S”##, will react with molten copper(I) oxide, ##”Cu”_2″O”##, to produce molten copper metal and sulfur dioxide, ##”SO”_2##.
Now, you know that your reaction must consume ##”20 g”## of copper(I) sulfide.
The first thing to do here is use the molar mass of copper(I) sulfide to convert the given mass to moles
##20 color(red)(cancel(color(black)(“g”))) * (“1 mole Cu”_2″S”)/(159.16color(red)(cancel(color(black)(“g”)))) = “0.1257 moles Cu”_2″S”##
Use the ##1:2## mole ratio that exists between the two reactants to find the number of moles of copper(I) oxide needed to ensure that all the moles of copper(I) sulfide react
##0.1257color(red)(cancel(color(black)(“moles Cu”_2″S”))) * (“2 moles Cu”_2″O”)/(1color(red)(cancel(color(black)(“mole Cu”_2″S”)))) = “0.2514 moles CU”_2″O”##
Use the molar mass of copper(I) oxide to convert this to grams
##0.2514 color(red)(cancel(color(black)(“moles Cu”_2″O”))) * “143.09 g”/(1color(red)(cancel(color(black)(“mole Cu”_2″O”)))) = color(green)(|bar(ul(color(white)(a/a)color(black)(“36 g Cu”_2″O”)color(white)(a/a)|)))##
Do the same for copper metal and sulfur dioxide. The reaction will produce
##0.1257 color(red)(cancel(color(black)(“moles Cu”_2″S”))) * “6 moles Cu”/(1color(red)(cancel(color(black)(“mole Cu”_2″S”)))) = “0.7542 moles Cu”##
This will be equivalent to
##0.7542 color(red)(cancel(color(black)(“moles Cu”))) * “63.546 g”/(1color(red)(cancel(color(black)(“mole Cu”)))) = color(green)(|bar(ul(color(white)(a/a)color(black)(“48 g Cu”_2″O”)color(white)(a/a)|)))##
I’ll leave the last calculation to you as practice.
I’ll leave both answers rounded to two , but keep in mind that you only have one sig fig for the mass of copper(I) sulfide.